Tranexamic acid (TA) has been proposed for preventing or treating primary postpartum haemorrhage (PPH), which is the leading cause of maternal morbidity and mortality worldwide. We conducted a systematic literature search to the TA role in managing PPH in vaginal and caesarean delivery. Twenty-seven randomised controlled trials (RCTs) (33,302 women) were identified. Three RCTs investigated TA for preventing PPH after vaginal delivery and 22 after caesarean section. None demonstrated a preventive effect on secondary clinical outcomes related to blood loss. Two trials evaluated TA for treating PPH after vaginal and caesarean delivery. Only the WOMAN trial showed that 1 g of TA is effective. In conclusion, TA is considered useful and is recommended or advised for treating PPH. Conversely, available evidence on the prophylactic role is still limited, and this use is not supported. Further investigation is recommended. In this regard, stronger and more reliable outcomes than blood loss should be considered.